论文标题
玻色子星的凝结和蒸发
Condensation and Evaporation of Boson Stars
论文作者
论文摘要
包括QCD轴在内的轴突状颗粒是动机的候选暗物质。数值模拟揭示了在轴突晕中心中的相干孤子构型，也称为玻色子星。我们研究浸入具有麦克斯韦速度分布的轴心波的轴孢子的演变。结合分析方法与受控的数值模拟，我们发现沉重的孤子子通过气体中的轴凝结而生长，而光孤子蒸发。我们推断出孤子生长/蒸发速率的参数依赖性，并表明它与气体中动力学松弛速率成正比。比例系数由孤子半径和典型气体动量的乘积控制，或者等效地，气体和孤子病毒温度的比率。当此参数大或小时，我们讨论了速率的渐近学。
Axion-like particles, including the QCD axion, are well-motivated dark matter candidates. Numerical simulations have revealed coherent soliton configurations, also known as boson stars, in the centers of axion halos. We study evolution of axion solitons immersed into a gas of axion waves with Maxwellian velocity distribution. Combining analytical approach with controlled numerical simulations we find that heavy solitons grow by condensation of axions from the gas, while light solitons evaporate. We deduce the parametric dependence of the soliton growth/evaporation rate and show that it is proportional to the rate of the kinetic relaxation in the gas. The proportionality coefficient is controlled by the product of the soliton radius and the typical gas momentum or, equivalently, the ratio of the gas and soliton virial temperatures. We discuss the asymptotics of the rate when this parameter is large or small.
